I'm rewatching DS9 and Quark just referred to "the brothers Quark" - which could mean that 1. In Ferengi society, theres no surnames but the older brother's name counts for both, 2. Quark doesn't want Rom's name mentioned anywhere in his business, or 3. Quark's full name is "Quark Quark"
The first one actually makes a lot of sense
It always bugs me whenever a fictional setting regards personal names as a unique enough identifier. It seams quite illogical that there are enough personal names for every member of the population to have a unique one (except when it is an intentional part of the world building which is not the case), so it is natural to assume there is some mechanism of identifying which John you're looking for, whether it's a surname, profession, patronim/matronim, place of birth etc. It is even more likely that Ferengi have one, as they are very big on contracts and help you God if you can't uniquely name one of the parties. It can be argued that they can use id numbers, fingerprints and such nowadays, but the need for identification almost certainly preceeds centralised numbered ids of any kind, so even if the mechanism is less relevant, it would still be in place at least as legacy.
Secondly, Ferengi seem to have something of a clan system ?? Idk how to put it, but when it transpires that Ishka is earning money Brunt clearly states that it's Quark's problem, as he is the head of the family, which obviously isn't just traditional but has some legal consequences. It is probably due to Ishka, a female, not having any legal agency and therefore needing a male proxy, but Ferengi still seem quite worked up about family ties, even if their family values are kind of different from ours, so it is possible that the "head of the family" thing includes not only female relatives, but also younger males.
So yeah, it might as well be that Quark and Rom used to be Keldar's Quark and Rom, but now that Keldar is dead Quark is just Quark and Rom and Ishka became Quark's Rom and Ishka.
Yeah that's always been my assumption. See also the way that when Nog got arrested in the first episode, Quark held himself responsible (Rom was nowhere to be seen, probably working though) for Nog's situation. He doesn't expect Nog to advocate for himself, and he doesn't expect Rom to advocate for Nog; no, he goes in and does the talking (and also the reprimanding, did you SEE the way he hissed at Nog?? Poor kid's in hot water). That makes a lot of sense if you assume Quark is the current head of the family
Also lol please don't leave the whole "Technically this makes Gaila Quark's Gaila despite him being more successful than Quark" thing in the tags bc that's a great and hilarious point!! Maybe that's part of why Gaila is always trying to screw Quark over; he feels like Quark is in his rightful spot as head of the family, so he keeps trying to get Quark out of the picture with rigged shuttles and such.
